I am Scott and I'm Then and we're from car Stuff. We're the podcast that covers everything that floats, flies, swims, or drives, adventures, thrills, chills literally, planes, trains and automobiles. That's right, And you can find all of our episodes on Google Play, Spotify, iTunes and really anywhere else you get your podcast. Welcome to brain Stuff from how Stuff Works. Hey, brain Stuff, this is Christian Seger. So night vision seems like a pretty cool idea, right, I mean, you see
it all the time in movies. Some secret agent type straps on a pair of goggles, sneaks into a luxurious supervillain compound and mows down enemies under the cover of darkness, or the Predator stocks Arnold Schwarzenegger killing his platoon one by one by one. And as you're watching all this, you may occasionally ask yourself, Hey, do those goofy looking
goggles really work? Well? The answer is yes, absolutely. With a good night vision device or n v D, you can see a person standing over two hundred yards or a hundred and eighty three meters away on a moonless, cloudy night. And whether we're talking goggles, scopes or cameras, Most of these devices rely on one or two types of night vision, image enhancement that's the green looking one, and thermal imaging, which is the bluish gray stuff. They
both produce results, but work in different ways. Thermal imaging captures the upper portion of the infrared light spectrum. Objects emit this as heat rather than reflecting it as light. Hotter objects, such as the bodies of secret agents, emit more of this light than cooler objects like buildings, trees, or you know, dead bodies, and that's what you're seeing when you use thermal imaging, essentially a measure of temperature from negative four degrees fahrenheit to three thousand and six
hundred degrees fahrenheit. The magic, or well, you know, the science starts at the lens, which focuses the infrared lightmitted by all of the objects in view and uses a phased array of infrared detector elements to create a temperature pattern called a thermogram, which is translated first into electric impulses and then into data for the display, where it appears as various colors depending on the intensity of the infrared.
Then there's image enhancement. This collects tiny amounts of light, including the lower portion of the infrared light spectrum and amplifies it. Devices using this approach rely on an image intensifier tube to collect and amplify light, both the infrared kind and the visible stuff. Image enhancers use a photo cathode to convert photons into electrons and high voltage to amplify those electrons in a micro channel plate or an m c P before they hit a screen that's coated
with phosphors. Here's the crazy part. These electrons maintain their position in relation to the micro channel they passed through, which provides a perfect image. Since the electrons stay in the same alignment as the original photons. When they hit the screen, their energy excites the phosphors, releasing photons. Those phosphors create the green image you see when you look
through a night vision scope. Check out the brain Stuffed channel on YouTube, and for more on this and thousands of other topics, visit how staff works dot com.